This invention relates generally to vehicles and more particularly to load lifting systems for low-profile underground mining vehicles having a main frame and a load-carrying device attached to the main frame.
Low profile underground mining vehicles are well known in the art and include a main frame and a load-carrying device such as a scoop, a bucket, a flat platform, a fork, or another similar load-carrying device pivotally attached to the main frame of the vehicle. Usually the lower rear end of the load carrying device is attached pivotally to the lower front end of the main frame of the vehicle, and a pair of hydraulic cylinders are attached between the upper rear end of the load-carrying device and the main frame for pivoting the load-carrying device. Such an arrangement provides only tilting of the load-carrying device and has two major limitations: first, the lift of the load is very limited, and second, during a load-lifting operation the angular position of the load, referring to ground surface, changes continually and cannot be corrected. The foregoing illustrates limitations known to exist in present load lifting systems. Thus, it is apparent that it would be advantageous to provide a alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.